Particles Containing a Non-Conducting or Semi-Conducting Nucleus Covered with a Hybrid Conducting layer, Their Processes of Preparation and uses in Electrochemical Devices

Patent metadata

Field	Value
Publication number	US-2020013561-A1
Application number	US-201916382704-A
Country	US
Kind code	A1
Filing date	Apr 12, 2019
Priority date	Jul 12, 2002
Publication date	Jan 9, 2020
Grant date	—

Abstract

Mixture of particles comprising a non-conducting or semi-conducting nucleus covered with a hybrid conductor coating and hybrid conductor chains located between the particles of the mixture to constitute a conductivity network, that is prepared by mechanical crushing. Due to a very good conductivity of the network, a low resistivity, a very good capacity under elevated current and/or a good density of energy, these mixtures of particles are advantageously incorporated in anodes and cathodes of electrochemical generators, resulting in highly performing electrochemical systems.

First claim

1 - 76 . (canceled)

77 . Mixture of particles comprising a non-conducting or semi-conducting nucleus, the nuclei of said particles being at least partially covered with a hybrid conductor coating and said particles being at least partially connected through hybrid conducting chains which provide a network of electrical conductivity, wherein:
the nucleus of said particles is at least 65% of one lithium oxide selected from the group consisting of oxides of the formula:
Li 4 Ti 5 O 12 ;
Li (4-α) Z α Ti 5 O 12 , in which 0<α≤0.33, Z represents a source of at least one metal; and
Li 4 Z β Ti (5-β) O 12 in which 0≤β≤0.5, Z represents at least one metal;
each of the hybrid conductor coating and the hybrid conducting chains is a hybrid carbon mixture which comprises at least two different conducting forms of carbon, which are hereunder designated Carbon 1 and Carbon 2, wherein:
Carbon 1 consists of particles with low crystallinity having a d002 greater than 3.36 Å if measured by X-ray diffraction or by Raman spectroscopy, said Carbon 1 possesses a specific surface area which, as measured by the BET method, is equal to or greater than 50 m 2 /g, and particles of Carbon 1 have an average size varying from 10 to 999 nm, and
Carbon 2 consists of at least one of graphite particles and high crystallinity carbon particles with high crystallinity having a d002 smaller than 3.36 Å if measured by X-ray diffraction, particles of Carbon 2 have a specific surface area which, as measured by the BET method, is equal to or smaller than 50 m 2 /g, and the particles of Carbon 2 have a size varying from 2 to 10 μm,
wherein the hybrid conductor coating comprises:
a first, inner coating of Carbon 1 which covers between 50 and 90% of the surface of the nucleus, and
a second, outer coating of Carbon 2.

78 . Mixture of particles according to claim 77 , in which the second, outer coating of Carbon 2 comprises particles are connected together to constitute an electrical conductivity network.

79 . Mixture according to claim 77 , in which the particles have a D 50 of about 7 micrometers.

80 . Mixture according to claim 77 , in which Z represents a particle of a metal selected from the group consisting of Mg, Nb, Al, Zr, Ni and Co.

81 . Mixture according to claim 77 , containing from 1 to 6% by weight of carbon in said mixture.

82 . Mixture according to claim 81 , containing about 2% by weight of carbon in said mixture.

83 . Mixture according to claim 77 , in which Carbon 2 is at least one graphite selected from the group consisting of synthetic graphite, natural graphite, exfoliated graphite and mixtures of two or more of these graphite.

84 . Mixture according to claim 77 , in which the weight percentage of Carbon 1 represents from 1 to 10% of the total weight of the coating composed of Carbon 1 and Carbon 2.

85 . Mixture according to claim 77 , in which the quantity of Carbon 1 is substantially identical to the quantity of Carbon 2.

86 . Mixture according to claim 77 , in which the average diameter of the nucleus of said particles varies from 50 nanometers to 30 micrometers.

87 . Mixture according to claim 86 , wherein the average diameter of said nucleus is of the order of about 2 micrometers.

88 . Mixture according to claim 77 , in which the average size of said particles, measured according to the electronic scanning microscope method, is between 4 and 30 micrometers.

89 . Mixture according to claim 77 , having at least one of the following properties: a very good local conductivity, a very good network conductivity, a low resistivity, a very good capacity under elevated current and a good density of energy.

90 . Mixture according to claim 87 , having a local conductivity, measured according to the four point method, that is higher than 10 −6 (Ohm-m).

91 . Mixture of particles according to claim 89 , having a network conductivity, measured according to the four point method, that is between 2.6×10 −3 and 6.2×10 −3 .

92 . Process for preparing a mixture of particles such as defined in claim 77 , comprising at least one of the following steps:
a) preparation of a mixture of at least one non-conducting or semi-conducting material with a conducting material, and the addition of a second conducting material to the mixture obtained; b) preparation of a mixture of at least one non-conducting or semi-conducting material with at least two conducting materials; and c) preparation of a mixture of conducting materials and mixing thereof with at least one non-conducting or semi-conducting material, wherein: the non conducting material is the lithium oxide; and the mixture is prepared by High Energy Ball Milling.

93 . Process for preparing a mixture of particles according to claim 92 , carried out at a temperature lower than about 300° C.

94 . Cathode for electrochemical generator comprising a mixture of particles as defined in claim 77 .

95 . Anode for electrochemical generator comprising particles as defined in claim 77 .

96 . Electrochemical generator of the lithium type including at least one metallic lithium anode and at least one cathode as defined in claim 94 .

97 . Electrochemical generator according to claim 96 , preferably of the rechargeable and/or recyclable type.

98 . Electrochemical generator of the lithium type including at least one metallic lithium anode as defined in claim 94 , at least one cathode and comprising at least one electrolyte.

99 . Electrochemical generator according to claim 96 , in which at least one anode and/or at least one cathode are provided with an aluminum current collector that is full or of the Exmet type (expanded metal).

100 . Electrochemical generator according to claim 96 requiring no previous preparation of the battery.

101 . Generator according to claim 96 , in which the electrolyte is a dry polymer, a gel, a liquid or a ceramic.

102 . Hybrid type supercapacitor comprising at least one electrolyte, at least one anode, as defined in claim 95 , and at least one cathode of the graphite or large surface area carbon type, requiring no previous preparation of the supercapacitor.

103 . Supercapacitor according to claim 102 , in which at least one anode and/or at least one cathode are provided with an aluminum current collector that is full or of the Exmet type (expanded metal).

104 . Supercapacitor according to claim 103 , in which the electrolyte is a dry polymer, a gel, a liquid or a ceramic.

105 . Electrochemical system according to claim 96 , wherein the electrode is prepared without any addition of additional carbon.

106 . Mixture according to claim 77 , in which at least some of the particles of Carbon 2 are connected together to constitute an electrical conductivity network.

107 . Mixture according to claim 77 , in which about 80% of Carbon 1 is covering the surface of said nuclei; and about 20% of the particles of Carbon 2 are connected together to constitute an electrical conductivity network.

108 . Mixture according to claim 77 , in which the nucleus of said particles consists for at least 70% of at least one metal oxide.

109 . Mixture according to claim 87 , having a local conductivity, measured according to the four point method, that is higher than or equal t

Assignees

• Hydro Quebec

Inventors

• Zaghib Karim
• Charest Patrick
• Guerfi Abdelbast
• Perrier Michel
• Kinoshita Kimio

Classifications

• Y02E60/13

  Energy storage using capacitors · CPC title

• B02C17/1815

  Cooling or heating devices · CPC title

• H01M4/366

  as layered products · CPC title

• H01G11/32

  Carbon-based · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title